It is well documented that yoga decreases stress hormones, like cortisol and increases GABA (gamma-Aminonbutyric acid) levels. GABA is an important calming chemical produced by the brain that counteracts anxiety and stress.
GABA is a major inhibitory neurotransmitter chemical in the brain.
GABA is responsible for balancing mood levels. It is believed that certain physical reaction disorders are due to the failure to produce adequate levels of GABA.
When GABA levels are maintained with breast cancer patients, physical stamina increases. Daily activities like climbing stairs, walking and doing the laundry become easier compared with those that don’t engage in a yoga practice or exercise.
GABA is very important for sustained recovery and optimal health.
Stress reduces the levels of GABA in our brains. The primary stress hormones, which inhibits GABA levels are cortisol, epinephrine, and norepinephrine. Cortisol is a steroid hormone that is manufactured in the adrenal glands and synthesized from cholesterol. They are small glands alongside to the kidneys. The hormone cortisol is released into the body during stress; hence it is called the "stress hormone." However cortisol is necessary for the overall function of the entire body. It is when there is an excess of cortisol that there is excess stress so when cortisol is secreted and remains in the bloodstream over prolonged periods of time, one may lose bone mass, or experience increased blood pressure, suppressed thyroid function, and weakened cognitive performance. The consequences of sustained cortisol levels include a compromised immune response as well as increased inflammation in the muscle tissue, hyperglycemia, and increased abdominal fat.
The proper balancing of the physical, and then emotional body are key to recovery, and good health. We need both but they need to be in balance, and yoga works directly at balancing them.